The present invention relates to a motorcycle brake system with a first hand-operated or foot-operated master brake cylinder for the hydraulic actuation of a first brake circuit and with a second hand-operated or foot-operated master brake cylinder for the hydraulic actuation of a second brake circuit.
JP 2000071963 A discloses a motorcycle brake system of this type. The brake system includes a hydraulically operable front-wheel and rear-wheel brake circuit in which brake pressure can be built up in the wheel brakes, jointly and independently of each other, by way of a foot-operated and hand-operated master brake cylinder. For brake slip control, electromagnetically activatable inlet and outlet valves and a dual-circuit pump drivable by an electric motor are mounted in the front-wheel and rear-wheel circuits. Furthermore, electrically operable separating valves and change-over valves are provided in the two brake circuits in addition to the inlet and outlet valves and the pump in order to likewise allow building up brake pressure in the brake circuit without manual operation in the event of manual operation of one of the two master brake cylinders, for what purpose the pump and the separating valve and change-over valve in the brake circuit which is not hand-operated are electrically activated.
One shortcoming of this brake system is the reactive effect of the pump pressure on the hand-operated master brake cylinder, with the result that pulsation can be sensed at the hand or foot brake lever of the manually operated master brake cylinder.
In view of the above, an object of the invention is to improve a motorcycle brake system of the type indicated in such a fashion that a reactive effect of the pump pressure on the hand-operated or foot-operated master brake cylinder can be reliably prevented by simplest possible and functionally reliable means.